The soldier's heart and the effort syndrome / by Thomas Lewis.

  • Lewis, Thomas, Sir, 1881-1945.
Date:
1918
Catalogue details

Licence: In copyright

Credit: The soldier's heart and the effort syndrome / by Thomas Lewis. Source: Wellcome Collection.

    46/164 (page 30)
    The chief sources of extra work for the heart in exercise are an accelerated heart action and a rise of mean blood pressure ; both of these phenomena are a part of the physiological circulatory response to the call. It is the regulating mechanism of the heart which increases the rate of that organ’s beating. It is the heart, in greater part at all events, which raises the arterial blood pressure by an increase of its own output. The circulatory organs are built to stand the strains which they themselves create ; their reserve is often under-estimated ; it is the full supply of blood to the muscles which will fail, and not the heart, when the call is excessive. How comes it that in the horse, the most heavily strained beast of burden, chronic heart affections are almost unknown ? A priori the hypothesis of heart strain is not reasonable. It is linked to the old tradition, that the first and last cause of heart failure is a mechanical defect ; that tradition is already moribund. As the hypothesis of heart strain has been applied to the soldier the actual evidence is all against it. The “ effort syndrome ” has been ascribed to heart strain ; the tight tunic, the belt, the shoulder strap, the pack, the long marches have in turn been called to account. The belief in cardiac strain was held more easily in the days when soldiers walked scores or hundreds of miles in the absence of quicker modes of transit. The physical strain imposed upon field troops in this war has been less than it has ever been in a great campaign before, yet the “ effort syndrome ” is as prevalent as it was, if not more so. It is present amongst troops in training as often as amongst those on front line duty ; nay, further, it develops in many civilians to whom strenuous exercise is and always has been unknown. So occasional is the soldier who positively dates the first onset of his symptoms in these days to an unusual strain, that this factor, as primal cause, recedes far into the background. Such a history was